University of Michigan, Ann Arbor, MI
Lawrence Livermore Laboratory, Livermore, CA
This report describes a general yield function for anisotropic elastoplastic materials written in a quadratic form in terms of the stress components. The function contains 28 independent coefficients that must be determined experimentally. A set of inequality constraint conditions imposed on these coefficients is derived from the convexity requirement for all yield functions. A number of previously derived yield functions are recognized here as special cases of the general quadratic yield function, and the convexity condition for each of them is also provided. These inequality conditions should aid experimental projects for material identification.
Paper ID: CTR10878J